animals  = ['cat', 'dog', 'fish']
a2 = ['tiger', 'lion']
animals.append(a2[0])
animals.append(a2[1])
print(animals)  #['cat', 'dog', 'fish', 'tiger', 'lion']

for animal in animals:
    print(animal,animals.index(animal))

str = 'hello'
for letter in str:
    print(letter,str.index(letter))

foods = ['烩面','饺子','牛排','馒头']
for food in foods:
    if food == '饺子':
        break
    print(food)

foods = ['烩面','饺子','牛排','馒头']
drinks  = ['水','茶','咖啡']
for food in foods:
    if food == '饺子':
        continue
    print(food)

foods = ['烩面','饺子','牛排','馒头']
drinks  = ['水','茶','咖啡']
num = 0

for food in foods:
    for drink in drinks:
       str = f'{food}搭配{drink}'
       print(str)
       num += 1
print(f'一共有{num}种搭配方式')